1. Field of the Invention
The disclosure relates to a stereo display apparatus, and particularly relates to an auto-stereoscopic display apparatus.
2. Description of the Related Art
The development of display technology not only aims at lightness, slimness, shortness, and compactness but also aims at the capability of displaying a stereo image. Currently, the technology of stereo display can be divided into the technology of stereoscopic display, with which the viewer has to wear a specifically designed eyeglass for viewing, and the technology of auto-stereoscopic display, with which the viewer is allowed to view with naked eyes.
Taking the technology of auto-stereoscopic display, a stereo display apparatus includes a display panel, which provides an image, and a liquid crystal lens array, which is disposed on an image-transmitting path. The liquid crystal lens array is utilized to respectively project the image provided by the display panel to the left and right eyes of a user, thereby forming a stereo image in human brain through binocular parallax generated after the two eyes respectively receive the image. Under an identical electric potential difference, the liquid crystal lens array has a constant value of effective focal length (EFL), making the stereo display apparatus have a single optimal view distance. In this way, when the user changes his/her view distance, his/her eyes become deviated from the optimal distance and therefore are unable to view a stereo image with an preferable effect of display.